Ladder for railroad cars



March 28, 1950 a. L. MILL-ER LADDER FOR RAILROAD CARS Filed June 10.1946 {8 I INVENTOR.

Geo/ye Lee Miller l 'd BY 29 2 ATTORNEY-5 Patented Mar. 28, 1950 UNITEDSTATES PATENT OFFICE 4 Claims.

The invention relates to ladders and more particularly to a one-piece,pressed steel ladder for use upon railroad cars.

, It is general practice to locate ladders upon the sides and ends ofall, box cars, gondolas, hopper cars and other railroad cars, in orderto provide easy access to trainmen to climb onto or descend from a carfrom either sideor either end thereof.

Under present practice these ladders are each made of a great number ofpieces which require. a considerable number of operations to form andassemble, adding greatly to the labor cost of producing such ladders.

As an example, the ladder commonly used upon box cars is generallyprovided with seven rungs and is attached to the car by six or morelugs. This requires the forming of the two stiles, the separate formingof seven rungs, and attaching of each end of each rung to the stiles asby rivets, the separate formingof six lugs, and the attaching of eachlug to one of the stiles of the ladder.

Not only does this involve considerable labor cost for all of theseseparate operations in the construction of a single ladder, but thestiles and rungs are formed of steel bars, producing a heavy structure,and since four of these ladders are required for each car, this addsmate,- riallyto the weight of the car. 4 Under the modern trend toincrease the speed of railroad trains it is necessary that the weight ofcars be reduced wherever this can be safely done.

The present invention therefore contemplates the provision of aone-piece ladder for railroad cars which may be formed in a minimum ofoperations, materially reducing the labor cost by production, and whichweighs only about onehalf the weight of the conventional railroad carladder, this considerably reducing the weight of each car.

Another object is to provide a. one-piece, pressed or stamped sheetsteel ladder which may be formed in a single operation.

A further object is to provide a ladder of this character in which thestiles, rungs and attaching lugs are all made from an integral sheet ofmetal formed so as to give the maximum strength.

A still further object is to provide such a ladder formed from a sheetblank of such shape as to provide for channel shape stiles and integral.tubular rungs and integral lugs for attaching the ladder to a car.

It is another object of the invention to provide a ladder of the typereferred to in which the attaching lugs are so formed asto increase thestrength of the structure.

A further object is to provide such a ladder which is so formed that ithas no protruding or projecting portions to interfere with the safe and.convenient use thereof.

The above objects, together with others which will be apparent from thedrawing and following description, or which may be later referred to,may be attained by constructing the improved ladder in the mannerhereinafter described in detail and illustrated in the accompanyingdrawing, in which:

Figure 1 is a plan view of the sheet blank from which the one-pieceladder is formed;

Fig. 2 a front elevation of a one-piece, pressed sheet metal ladderconstructed in accordance with the invention; I

Fig. 3 a fragmentary, longitudinal section through one end portion ofthe ladder, taken on the line 33, Fig. 2;

- Fig. 4 a transverse section through the ladder taken on the line 4-4,Fig. 2;

Fig. 5 a fragmentary rear elevation of a portion of the ladder, and;

Fig. 6 a transverse sectional view through a slightly modified form ofthe improved ladder showing one attaching lug bent inward and theopposite lug bent outward to further strengthen the structure.

The entire ladder comprising the stiles, rungs and attaching lugs isformed in one piece from a single sheet of steel of suitable gauge, bystamping a sheet blank of proper configuration, as indicated generallyat II] in Fig. 1, and forming said blank into the ladder, as indicatedgenerally at I! in Fig. 2.

Both the stamping and forming operations may be carried out in asuitably constructed die for preforming the same in a single, continuousoperation, or the blank Ill may be first stamped in a stamping die andthen removed to a forming die in which the ladder, asindicated at H, maybe formed.

The blank [0, shown in Fig. 1, comprises the two spaced, longitudinalside portions 12, for forming the stiles l3 of the ladder, terminatingat opposite ends in the reduced portions l4 having rounded ends l5, forforming the reduced, curved upper and lower terminal ends l6 of thestiles I3 of the ladder; the uniformly spaced, straight, horizontalportions I1 extending betweenthe vertical side portions l2, for formingthe rungs [8 of the ladder; and the substantially triangular lugs l9extending inwardly from the vertical side portions H2, at points nearthe center and each end of the blank, for forming the attaching lugs 20of the ladder.

The ladder ends 16 are curved as shown in Fig. 5 and terminatesubstantially in the plane of the rear sides of the attaching lugs 20,so as to fit flush with the car roof at the top end and at the bottom tofit flush with the side or end sill of the car body to reduce thepossibility of accidents.

Rounded ends 2l are preferably formed upon the ears t9, and apertures 22are punched therein to provide means for attaching the ladder to theside or end wall of a freight car by inserting screws, bolts or the liketherethrough.

In the drawing a seven rung ladder is shown, this being the lengthordinarily used upon box cars. A pair of attaching lugs is shown belowthe upper rung and a pair above the lower rung, while a pair of lugs isshown on each side of the central rung of the ladder. This arrangementof attaching lugs may be varied as desired. For instance, instead oflocating two lugs on each side of the central rung, one lug may beprovided above this rung as an integral part of the inside flange of onestile and another lug below the central rung as an integral part of theinside flange of the other stile.

The sheet metal blank shaped as illustrated and above described ispressed in the dies into the completed ladder as shown in 2. forming ofthe blank the vertical side portions i2 of the blank are pressed intochannel shape to form the stiles it of the ladder having the relativelywide inturned flanges 23 at their outer edges and the relatively narrowinturned flanges 24 at their inner edges.

The ears H] of the blank which form extensionsupon the inner flanges 24of the side rails are bent downwardly as at 25 and inwardly as at 26,being so positioned that when attached to the side or end wall of a carby bolts or the like located through the apertures 22, they will supportthe ladder in vertical position correctly spaced from the wall of thecar.

At the same time the horizontal straight portions H of the blank arepressed into tubular shape forming the tubular rungs iii integrally apart of the stiles [3.

Instead of bending the lugs on both sides of the ladder inward as shownin Figs. 2 and 4, the lugs on one side may be bent inward and those onthe other side bent outward as indicated in Fig. 6, wherein the lug atthe right hand side is bent downward and outward at an angle asindicated at 25a, the lower perforated end thereof being then bentoutward in a plane parallel to the lower plane of the ladder asindicated at 26a.

To further strengthen the structure, the attaching lug shown at the lefthand side of Fig. 6 may bent downward and slightly outward as indicatedat 2519, the terminal end thereof being bent inward as at 26?) in aplane parallel to the normal plane of the ladder.

Ladders made in this manner from .a single sheet of metal in a singlestamping and forming operation eliminates the many operations requiredfor the making of conventional ladders for this purpose, thus greatlyreducing the .labor cost of producing a freight car ladder.

Furthermore the sheet metal required for producing a ladder of this typehaving suflicient strength for the purpose for which it is intendedweighs only about 50% of the weight of the conventional ladder, thusalso reducing the cost as well as the weight of the material.

It will be noted that the ladder as described and shown presents astructure that offers much from the standpoint of safety. It is smoothand clean throughout its entire structure, there being no projections orobstructions such as irregular In this shapes, rivet heads, sharpcorners and the like to interfere and since it is an integral structurethere are no joints to come loose or get out of alignment when inservice.

I claim:

1. A one-piece sheet metal ladder of the character described comprisingtwo spaced, straight, longitudinal side portions terminating at opposideends in reduced extensions, uniformly spaced, straight transverselydisposed portions extending between the longitudinal side portions andsubstantially triangular lugs extending inwardly from the longitudinalside portions between certain of the transverse portions, thelongitudinal side portions forming channel stiles, the reducedextensions forming rearwardly curved terminal ends of the stilesterminating substantially in the plane of the rear side of the ladder,the transversely disposed portions forming hollow rungs and thetriangular lugs forming integral, angular attaching lugs extendingrearwardly from the inner flanges of the stiles and being an integralpart thereof.

2. A sheet metal ladder of the character described comprising twostraight, longitudinal stiles each having rearwardly disposed flanges atits outer and inner sides, rearwardly disposed triangular extensionsformed integrally with the inner side flanges and having angularlydisposed terminal ends forming integral attaching lugs, integral hollowrungs connecting the stiles, and rearwardly curved integral extensionsupon the upper and lower ends of the stiles terminating substantially inthe plane of said attaching lugs.

3. A metal ladder of the character described comprising two straight,longitudinal stiles each having rearwardly disposed flanges at its outerand inner sides, rearwardly disposed triangular extensions formedintegrally with the inner side flanges and having angularly disposedinturned terminal ends forming integral attaching lugs, integral hollowrungs connecting the stiles, and rearwardly curved integral extensionsupon the upper and lower ends of the stiles terminating substantially inthe plane of said attaching lugs.

4. A metal ladder of the character described comprising two straight,longitudinal stiles each having rearwardly disposed flanges at its outerand inner sides, rearwardly disposed triangular extensions formedintegrally with the inner side flanges and having angularly disposedoutturned terminal ends disposed in the rear of the outer side flangesof the stiles forming integral attaching lugs, integral hollow rungsconnecting the stiles, and rearwardly curved integral extensions uponthe upper and lower ends of the stiles terminating substantially in theplane-of said attaching lugs.

GEORGE LEE MILLER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 902,331 Ryan Oct. 2'7, 19081,196,667 Dallmeyer Aug. 29, 1916 1,215,455 Wine Feb. 13, 1917 1,714,451Suavage May 21, 1929 1,872,680 Chiles Aug. 23, 1932 1,952,878 MarschutzMar. 27, 1934

